MS
Teams
(please
email
amgrad@uwaterloo.ca
for
the
meeting
link)
Candidate
Mahdi Yavarian | Applied Mathematics, University of Waterloo
Title
Modeling of Charging Dynamics in Electrochemical Systems with a Graphene Electrode
Abstract
The graphene/electrolyte interface plays a critical role in many promising applications, such as supercapacitors and biosensors. The graphene/electrolyte interface is often modeled as two capacitors in a series connection: the Debye capacitance and the quantum capacitance of graphene, in which the quantum capacitance of graphene dominates the total capacitance. While several reports have focused on studying the capacitance of graphene as a function of the gate voltage, the mathematical modeling associated with the frequency response of the graphene/electrolyte interface has yet to be appreciably explored. To this end, electrochemical impedance spectroscopy is one of the many electrochemical techniques helpful in assessing various electrochemical processes occurring at the electrode interface, including double-layer charging, charge transfer, mass transport, adsorption/desorption process, and the ability to distinguish several electrochemical time scales. In this research proposal, the main goal is to develop a well founded mathematical model of the frequency response of graphene/electrolyte interface for the least explored yet essential problems such as the interaction of ionic liquids with graphene electrode, 1/f noise behavior in graphene, finite conductivity of graphene, and elusive behavior of constant phase element at the surface of the graphene/electrode. The results are expected to offer insight into the design and analysis of devices involving the graphene/electrolyte interface for supercapacitor and bioelectronics applications.